Transcript (light) reactions

review material
chapters two & five
acids & bases
• acid
– dissociates into H+
– HCl  H+ + Cl
• base
– dissociates into OH
– NaOH  Na+ + OH
Figure 2.6
acid-base balance
• H+ in solution expressed as pH
– pH = -log [H+]
– increasing [H+]
increases acidity
– increasing [OH-]
increases alkalinity
Figure 2.7
Energy Requirements of a Chemical
Reaction
Figure 5.2
The Mechanism of Enzymatic Action
Figure 5.4a
Factors Influencing Enzyme Activity
• Temperature
• pH
• Substrate concentration
• Inhibitors
enzyme activity
• enzymes denatured by temperature and pH
Figure 5.6
Figure 5.5b
Figure 5.5a
Enzyme Inhibitors: Competitive Inhibition
Figure 5.7a–b
Enzyme Inhibitors:
Noncompetitive/Allosteric Inhibition
Figure 5.7 a, c
Enzyme Inhibitors: Feedback Inhibition
Figure 5.8
chemical reactions
• making or breaking of bonds between atoms
– result in change in chemical energy
– potential
kinetic energy
• exergonic reactions release energy
A–B
A

Molecule
AB
Atom, ion,
or molecule A
+
B
Atom, ion,
or molecule B
• endergonic reactions absorb energy
A
Atom, ion,
or molecule A
+
B
Atom, ion,
or molecule B

A–B
New molecule
AB
carbohydrate catabolism
• the breakdown of carbohydrates to release energy
– glycolysis
• oxidation of glucose to pyruvic acid, produces ATP and NADH
– Krebs cycle
• oxidation of acetyl CoA, produces NADH and FADH2
– electron transport chain
• serial carrier molecules that are oxidized and reduced as electrons
are passed down the chain
• released energy can be used to produce ATP by chemiosmosis
Photosynthesis
• Photo: Conversion of light energy into
chemical energy (ATP)
– Light-dependent (light) reactions
• Synthesis:
– Carbon fixation: Fixing carbon into organic
molecules
– Light-independent (dark) reactions